The subject matter herein relates to connections between optical and electrical devices.
In computerized storage systems, it is often necessary to connect one or more storage devices to a host computer, such as a storage server. In a Fibre Channel system, for example, the host computer commonly connects through a fiber optic cable to the storage devices. The host computer typically sends optical signals through the fiber optic cable to the storage devices, where the optical signals are converted into electrical signals for transfer through common wiring, such as copper wires, to the storage devices. The storage devices are commonly connected in a group referred to as a xe2x80x9cJBODxe2x80x9d (Just a Bunch Of Disks). Typical JBODs have up to eight storage devices connected to a xe2x80x9cbackplane,xe2x80x9d which connects to the fiber optic cable. Thus, the JBODs are limited in the number of storage devices that can be connected together.
For connecting a single storage device through the fiber optic cable to the host computer at a 1-Gbit/sec transfer rate, a connector cable 100 has been developed, as shown in FIG. 1. The connector cable 100 is of the type commonly referred to as a xe2x80x9cpigtailxe2x80x9d and includes a conventional DB9 connector 102 connected to conventional transmit and receive connectors 104 and 106, respectively. The DB9 connector 102 connects through a media interface adapter (not shown) to the fiber optic cable (not shown). The transmit and receive connectors 104 and 106 connect to the storage device (not shown) or to a conventional Fibre Channel xe2x80x9cT-Cardxe2x80x9d (not shown), which connects to the storage device. The media interface adapter converts the optical signal used by the fiber optic cable to the electrical signal used by the connector cable 100. To do so, however, the media interface adapter requires electrical power. Therefore, the connector cable 100 also includes two conventional power connectors 108 and 110, one of which is connected to an electrical power source (not shown). The power connectors 108 and 110 connect to the DB9 connector 102 to supply the electrical power to the media interface adapter. The connector cable 100 is limited to working with only one storage device and is not supported in recent standards set by the Fibre Channel Standards Committee for 2-Gbit/sec transfer rates.
It is with respect to these and other background considerations that the subject matter herein has evolved.
The subject matter herein involves a new and improved connector cable (sometimes referred to as a xe2x80x9cpigtailxe2x80x9d) for connecting a host computer (e.g. a storage server) through a fiber optic cable to any number of storage devices connected together in a chain-like fashion through the connector cable at the new 2-Gbit/sec rate set by the Fibre Channel Standards Committee. The connector cable also generally includes electrical power connectors for electrical power to support a media interface adapter (MIA) in an environment that provides both wire (e.g. copper, etc.) and optical interconnectivity. With the electrical power, the MIA converts signals that pass therethrough from optical to electrical and vice versa.
The connector cable also generally includes a pass-through mechanism so that any number of the storage devices can be chained together, rather than being limited to the number of storage devices that can be inserted into the backplane of a JBOD. For the pass-through mechanism, in one embodiment, the connector cable includes two transceiver connectors connected together. One of the transceiver connectors is for connecting to the MIA (and thus to the fiber optic cable), and the other transceiver connector is for chaining, or connecting, to a next storage device (possibly through another similar connector cable). Additionally, one of the transceiver connectors is also for connecting to a receiver connector connected to the storage device, and the other transceiver connector is also for connecting to a transmitter connector connected to the storage device. In this manner, a signal from the host computer that comes to the connector cable through the fiber optic cable is passed from the first transceiver connector to the receiver connector and the storage device connected thereto and/or to the second transceiver connector and the next storage device, if any.
In one embodiment, the connector cable preferably uses a conventional HSSDC (High Speed Serial Device Connector) connector, instead of a DB9connector, to connect to the MIA and to pass the electrical power to the MIA, since the HSSDC connector is supported by the new 2-Gbit/sec standards set by the Fibre Channel Standards Committee. In a more particular embodiment, the connector cable uses two of the HSSDC connectors as the two transceiver connectors to enable the pass-through mechanism.
A more complete appreciation of the present disclosure and its scope, and the manner in which it achieves the above noted improvements, can be obtained by reference to the following detailed description of presently preferred embodiments taken in connection with the accompanying drawings, which are briefly summarized below, and the appended claims.